Tanning apparatus



(No Model.) 2 Sheets-Sheet 1. L. SIMPSON.

TANNING APPARATUS.

Patented Dec. 15, 1885.

2 Sheets-Sheet 2.

(No Model.)

L. SIMPSON. TANNING APPARATUS BEES.

M 1 WW I UNITED STATES PATENT Fries.

LENOX SIMPSON, OF BELLEVUE, ALLEGHENY COUNTY, PENNSYLVANIA.

TANNING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 332,450, dated December15, 1885.

Application filed April 22, 1885.

To all whom it may concern.-

Be it known that I, LENOX SInrsoN, a citizen of the United States,residing at Bellevue borough, in thecounty of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inTanning Apparatus, of which the following is a full, clear, and exactdescription.

This invention relates to improvements in apparatus for carrying out theprocess of tanning describedand claimed in my application for LettersPatent of the United States filed the 12th day of November, A. D. 1881,and bearing the Serial No. 1 7,757. In said application a process oftanning is described which consists, essentially, in alternatelycompressing the tannic liquor into the hide until its acid haschemically combined with the gelatine, and immediately thereafterdrawing out of the pores the spent liquid by avacuum, these steps beingalternated in rapid succession until the hide is sufficiently tanned.

The object of the present invention is, first, to immerse the hide inliquor and apply pressure, then remove the liquor and exhaust the air,and alternate these steps rapidly and automatically until the hide istanned; second, to utilize the tannic liquor during the time when it isremoved from the vat; third, to regulate the degree of pressure andevacuation of the air within the vat; and, fourth, to an tomaticallyshift the liquor back and forth between two vats.

The invention consists, first, in air-tight twin vats connected at theirbases, said connections provided with a valve, by opening which theliquor may be shifted from one vat to the other; second, in a cylinderconnected at one end with theinterior of one vat and at the other endwith the interior of the remaining vat,said cylinder being provided witha. piston adapted to work the valve between the vats; third, in acompression-pump and a vacuum-pump, each pump connected by a pipe withboth vats, and a device which alternately brings each pump intocommunication with each vat; fourth, in a valve-chest provided with fourports, one of the aforementioned pump-pipes being connected with each ofsaid ports, a valve adapted to open and close said ports in propersequence, and means for operating said Valve; and, fifth, in variousdetails of construc- Serial No. 163,023. (No model.)

tion, all of which will be hereinafter more fully described.

In the drawings, Figure 1 represents a top plan view of my improvement;Fig. 2, a side elevation partly in section, and partly broken away toshow the interior of one of the vats; Figs. 3, 4, 5, 6, sectional viewsof the valvechest, showing the valve in the four different positions itoccupies during the operation; Fig. 7, a longitudinal vertical sectionof the valve lying between the two vats; Fig. 8, a longitudinaltransverse section of same; Fig. 9, a vertical transverse section ofsame.

Similar letters of reference indicate corresponding parts throughout thedifferent views.

A A are two vats, which may be of any size, shape, or material, providedthey be sufficiently strong to bear an external pressure of anatmosphere and an internal pressure of upward of thirty pounds to thesquare inch, and that they be constructed of such material as will notdiscolor the leather when acted on by tannic acid. I prefer to constructsaid vats of wood and properly brace them. The vats are beveled on theirupper inner edges, and provided with lids or tops, also beveled on theiredges. The tops are wedged down, or may be secured in any otherconvenient manner which will insure atight joint. A rubber or othergasket may be interposed between said top and vat. The vats may beseparate or built together, as shown in the drawings, and separated onlyby a partition. I11 case the vats are made entirely separate, I connectthem at the bottom by suitable pipes or ducts provided with cocks; butas I prefer to construct them, for reasons of economy and convenience,together, with merely a partitionwall between, I will confine mydescription to that form of vat.

In the bottom of the partition wall a, I secure avalve-casing, a,providedwith a large number of ports, a In this casing works aslide-valve, B, provided with ports 7), equal in number and size tothose in the casing a. It will be seen that by this construction whenthe valve is forced in either direction from a closed position theinteriors of the vats will communicate. A rod, b, connects the ex.-

tremity of said valve with one end of a slotted lever, D. Said lever isfulcrumed a short dis tance above its point of connection with theremaining portf with the vat A.

3 the opposite side of said chest.

55 with a spring-bolt, Z.

valve-rod, and has its free extremity slotted.

and connected with one end of the piston E. Said piston is provided witha head within the cylinder F. The latterhas near its ends pipes 5 ff,which connect it with the interior of vats lo bear upon one side of thepiston-head, and the latter is moved, thereby forcing piston E in onedirection or the other, and through the medium of the level-D and rod 12moving the slide-valve b. The piston E at one extremity 1 is connectedwith a slide-valve, E, which works in a valve chest, F. Said valve isprovided with two ports, f f, and said valvechest has on either sidefour (4) ports,ff ff G G are the exhaust and compression pumps Qrespectively. The pump G is provided with a safety-valve, Gflwhich maybe set to any desired number of pounds pressure. From the pump G a pipe,9, extends to the valve-chest F",where it is divided into two branches,one

of which is connected with port f upon one side of the valve chest, andthe other with port f upon the opposite side of the valvechest. A pipe,H, connects remaining port f with the vat A, and a pipe, H, connects theFrom the pump G a pipe, 9, extends to the valve-chest E, where it isdivided into two branches, one

of which enters port f upon one side of the chest, and the other entersthe port f upon A pipe, H connects the remaining port f with the vat A,and a similar pipe, H connects the remaining port f 6 with the vat A. Bythis constructionit will be seen that each of the pumps 0 is connectedwith both vats and that the position of the valve F determines which vatshall be in communication with a particular pump. Upon the upper side ofthe piston E is a lug, e, which extends upward through a slot, 0, in

4 5 the casing K. Said slot determines the length of stroke of thepiston. To the upper extremity of lug e are secured twocounterbalancingsprings, e eflwhose office is to force the piston-headand slide-valves toward a middle position when the pressure in thecylinder is equal upon each side of the head. Upon the lower side ofsaid piston are three lugs, e e e. Beneath the piston-rod are a seriesof catches, L L L L Each of said catches is provided Stops Z limit themotion of the catches in one direction. The catches L L are intended tocatch and hold the piston at the ends of its stroke. The catches L L nnybe provided with arms Z Z set at an obtuse angle, and having their freeextremities connected with the curved pistons Z P. The latter work incylinders M M,which have their extremities connected by a small pipe, m,and are filled with water or other liquid.

Attached to the catches L L L L are coilsprings Z Z Z Z". The springs ZZ have a tension somewhat less than that possessed by the springs e 6when the lugs e e are caught over the catches L L The springs Z Z areset at a tension equal to the pressure upon one side of the piston-headin cylinder F when the desired compression is bad in one vat and exhaustin the remaining vat. The function of the catches is to, hold the valvesin proper relation to the ports in the valve-casings at each step of theoperation. The function of the arms Z P, pistons Z P, and cylinders M Mis to prevent the lugs c e from dragging over the tops of the catches LL by virtue of their momentum. Said arms, pistons, and cylinders areoptional and may be dispensed with,

if so desired.

Instead of springs Z Z Z Z", cords, pulleys, and weights may be used,and, indeed, the catches L L, with their springs Z K", may be done awaywith altogether if the mechanism be constructed to work with delicacy.

The operation of the invention is as follows: The hides are hung in bothvats so that about one-third (3 of the upper part of each vat remainsunoccupied. The safety-valve upon pump G is set to the amount ofpressure desired within the vats. The springs b b are set to stand aweight equal to the sum of the pressure upon one side of the piston-headplus the exhaust upon the other side of said head. The piston is thenpushed inward until the lug e rests against the outer side of the catchL. Sufficient tannic liquor is then introduced into vat A to cover thehides and the lids are wedged upon the tops of the vats. At this timeslide-valve B cuts off communication between the two vats. Theslide-valve F is in the position shown in Fig. 4that is to say, vat A isin communication with the pump G and vat A in communication with thepump G. The pumps are then operated and the air within the vat Acompressed, while that within the vat A is exhausted. By this step Idrive the tannic liquor into the skins in vat A, while at the same timeI expand and open the pores of the skins within vat A.' When thecompression in vat A plus the exhaust in vat A exceeds the pressurewhich the spring Z is set to withstand, the lug 6 will drag over thecatch L and the piston will be forced outward to the end of itsstroke,where it is held in place by the lug e and catch L. At the sametime the slide-valve B has been pushed farther into the valve-casing ofthe vats and communication between the vats established. At this step inthe operation the slide-valve F is in the position shown in Fig. 5thatis to say, all communication between the vats and pumps is shut off. Thevat A being partially filled with compressed air and the vat A beingexhausted of its air, the liquor within vat A will be forced into vat Awith great rapidity. When all the liquor (and some of the air) haspassed into vat A, the pressure in the two vats (and upon the oppositesides of the piston-head within cylinder F) becomes equal. Thereupon thespring 6 drags the lug 6* over the catch L and. forces IOC the pistoninward until the lug e rests against the catch L. Communication betweenthe vats is thereby cut off, and the slide-valve F is then in theposition shown in Fig. 6. The

exhaust-pum p is then in communication with vat A and thecompression-pump with vat A. When the compression in vat A plus theexhaust in vat A exceeds the pressure which the catch Lis set towithstand,the lug e is dragged over said catch and the piston E isforced inward to the end of its stroke, where it is held by catch L Thismovement of the piston causes valve B to open communication between thevats and the valve Fto shut off communication between the vats andpumps, as shown in Fig. 3. The liquor is then shifted from vat A to A inthe manner already described. The operation thus proceeds: the liquorshifted back and forth between the two vats, compression always broughtto bear in the vat containing liquor, and a vacuum always formed in thevat devoid of liquor as long as the pumps continue to work. From time totime the liquor is run off and stronger fresh liquor substitutedtherefor. I thus dispense with all handling of the hides after beinghung in the vat. The constant shifting of the liquor keeps it properlyagitated, and the alternate pressing of the liquor into the skin andinstantaneous re-' moval of the spent liquor shortens the process oftanning to about thirty-six hours for calfskins and proportionately forheavier hides.

Having thus described my invention, what I claim is 1. The combination,with the two vats A A, separated by a partition, of the casing a, havingports a", and the slide-valve B, having ports I), as and for the purposedescribed.

2. The combination, with the vats A A, casing a, and slide-valve B, ofthe endslotted lever D, having a rod-connection with said valve end, thepiston E, connected with the slotted end of lever, and the cylinder F,having pipesffnear its ends, as and for the purpose specified. A

3. In a tanning apparatus in which airpumps are employed, thecombination, with two air-tight vats provided with valved connections attheir bottoms, of a cylinder having one end connected with one of saidvats and the other end connected with the remaining vat, a pistonworking in said cylinder and connected with the valves of the vats, andmechanism for regulating the movement of said piston, whereby thedifference in pressure within the two vats operates said valves,substantially as and for the purposes described.

4. The combination, with the two air-tight vats and an exhaust andcompression pump, of a cylinder, one end of which is connected with oneof said vats and the other end with the remaining vat,a valve-chestprovided with four entrance and four exit ports, said ports connectedwith the pumps and vats, respectively, a valve adapted to open and shutsaid ports, a piston working in said cylinder and adapted to operatesaid valve, and mechanism for regulating the movement of said piston,substantially as and for the purposes described.

5. The combination of two air-tight vats provided at their bottoms withvalved connections, exhaust and compression pumps, a valve-chest havingfour entrance and four exit ports connected with the pumps and vats, respectively, and provided with a valve adapted to open and close saidports, a cylinder, one extremity of which is connected with one of thevats and the other extremity with the re maining vat, a piston workingin said cylinder and connected with all the valves, and mechanism forregulating the piston, substantially as and for the purposes described.

6. The combination,with two airtight vats provided at their bottoms withvalved connections, exhaust and compression pumps, a valve-chest havingfour entrance and four exit ports connected with the pumps and vats, respectively, and provided with a valve, and a cylinder,one of whoseextremities isiu communication with one of the vats and the otherextremity with the remaining vat, of a piston working in said cylinderand provided with lugs, and catches adapted to engage with said lugs andregulate the movement ofsaid piston, substantially as and for thepurposes set forth.

7. The combination of vats A A, provided .with valve-casing a and valveB, cylinder F,

pipes f f, piston E, having lugs e e e c", springs e e, catches L Llever D, and pumps G G, connected with the vats, substantially asdescribed, whereby, when the difference in pressure within the two vatsis sufficient to overcome the resistance of the catches L L", the valvebetween the vats will be opened and the liquor shifted into the emptyvat, for the purposes set forth.

8. The-combination of vats A A, provided with valve-casing a and valveB, cylinder F, pipes ff, piston E, having lugs c e e c, springs e 0catches L L L L, lever D,valvecasing F valve F, pumps G G, and pipes g gH H H H substantially as described, whereby the liquor is shifted backand forth between the vats, pressure applied to the vat containingliquor, and the air exhausted from the vat devoid of liquor, for thepurposes set forth.

LENOX SIMPSON.

\Vitnesses:

W. D. THOMAS, CHAS. R. BULGER.

